early 2000’s maybe. American Horror/Comedy movie. It was a video rental.
Basically, a Heavy Metal band goes to the country to record and the Bass player finds a piece of sheet music and plays it backwards and summons zombies. I remember one scene where a boy and girl must escape the house filled with zombies and the only way they can accomplish this is to pretend to be zombies themselves, and it works.
Deathgasm (2015)?
“Rock ‘n’ Roll Nightmare” (1987)?
https://www.imdb.com/title/tt0093873/?ref_=nv_sr_2